// Copyright (c) 2013 Pieroxy // This work is free. You can redistribute it and/or modify it // under the terms of the WTFPL, Version 2 // For more information see LICENSE.txt or http://www.wtfpl.net/ // // For more information, the home page: // http://pieroxy.net/blog/pages/lz-string/testing.html // // LZ-based compression algorithm, version 1.4.2 var LZString = { // private property _f: String.fromCharCode, _keyStrBase64: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", _keyStrUriSafe: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-$", _getBaseValue: function (alphabet, character) { if (!LZString._baseReverseDic) LZString._baseReverseDic = {}; if (!LZString._baseReverseDic[alphabet]) { LZString._baseReverseDic[alphabet] = {}; for (var i = 0 ; i < alphabet.length ; i++) { LZString._baseReverseDic[alphabet][alphabet[i]] = i; } } return LZString._baseReverseDic[alphabet][character]; }, compressToBase64: function (input) { if (input == null) return ""; var res = LZString._compress(input, 6, function (a) { return LZString._keyStrBase64.charAt(a); }); switch (res.length % 4) { // To produce valid Base64 default: // When could this happen ? case 0: return res; case 1: return res + "==="; case 2: return res + "=="; case 3: return res + "="; } }, decompressFromBase64: function (input) { if (input == null) return ""; if (input == "") return null; return LZString._decompress(input.length, 32, function (index) { return LZString._getBaseValue(LZString._keyStrBase64, input.charAt(index)); }); }, compressToUTF16: function (input) { if (input == null) return ""; return LZString._compress(input, 15, function (a) { return String.fromCharCode(a + 32); }) + " "; }, decompressFromUTF16: function (compressed) { if (compressed == null) return ""; if (compressed == "") return null; return LZString._decompress(compressed.length, 16384, function (index) { return compressed.charCodeAt(index) - 32; }); }, //compress into uint8array (UCS-2 big endian format) compressToUint8Array: function (uncompressed) { var compressed = LZString.compress(uncompressed); var buf = new Uint8Array(compressed.length * 2); // 2 bytes per character for (var i = 0, TotalLen = compressed.length; i < TotalLen; i++) { var current_value = compressed.charCodeAt(i); buf[i * 2] = current_value >>> 8; buf[i * 2 + 1] = current_value % 256; } return buf; }, //decompress from uint8array (UCS-2 big endian format) decompressFromUint8Array: function (compressed) { if (compressed === null || compressed === undefined) { return LZString.decompress(compressed); } else { var buf = new Array(compressed.length / 2); // 2 bytes per character for (var i = 0, TotalLen = buf.length; i < TotalLen; i++) { buf[i] = compressed[i * 2] * 256 + compressed[i * 2 + 1]; } var result = []; buf.forEach(function (c) { result.push(String.fromCharCode(c)); }); return LZString.decompress(result.join('')); } }, //compress into a string that is already URI encoded compressToEncodedURIComponent: function (input) { if (input == null) return ""; return LZString._compress(input, 6, function (a) { return LZString._keyStrUriSafe.charAt(a); }); }, //decompress from an output of compressToEncodedURIComponent decompressFromEncodedURIComponent: function (input) { if (input == null) return ""; if (input == "") return null; input = input.replace(/ /g, "+"); return LZString._decompress(input.length, 32, function (index) { return LZString._getBaseValue(LZString._keyStrUriSafe, input.charAt(index)); }); }, compress: function (uncompressed) { return LZString._compress(uncompressed, 16, function (a) { return String.fromCharCode(a); }); }, _compress: function (uncompressed, bitsPerChar, getCharFromInt) { if (uncompressed == null) return ""; var i, value, context_dictionary = {}, context_dictionaryToCreate = {}, context_c = "", context_wc = "", context_w = "", context_enlargeIn = 2, // Compensate for the first entry which should not count context_dictSize = 3, context_numBits = 2, context_data = [], context_data_val = 0, context_data_position = 0, ii, f = LZString._f; for (ii = 0; ii < uncompressed.length; ii += 1) { context_c = uncompressed[ii]; if (!Object.prototype.hasOwnProperty.call(context_dictionary, context_c)) { context_dictionary[context_c] = context_dictSize++; context_dictionaryToCreate[context_c] = true; } context_wc = context_w + context_c; if (Object.prototype.hasOwnProperty.call(context_dictionary, context_wc)) { context_w = context_wc; } else { if (Object.prototype.hasOwnProperty.call(context_dictionaryToCreate, context_w)) { if (context_w.charCodeAt(0) < 256) { for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } } value = context_w.charCodeAt(0); for (i = 0 ; i < 8 ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } else { value = 1; for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1) | value; if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = 0; } value = context_w.charCodeAt(0); for (i = 0 ; i < 16 ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } context_enlargeIn--; if (context_enlargeIn == 0) { context_enlargeIn = Math.pow(2, context_numBits); context_numBits++; } delete context_dictionaryToCreate[context_w]; } else { value = context_dictionary[context_w]; for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } context_enlargeIn--; if (context_enlargeIn == 0) { context_enlargeIn = Math.pow(2, context_numBits); context_numBits++; } // Add wc to the dictionary. context_dictionary[context_wc] = context_dictSize++; context_w = String(context_c); } } // Output the code for w. if (context_w !== "") { if (Object.prototype.hasOwnProperty.call(context_dictionaryToCreate, context_w)) { if (context_w.charCodeAt(0) < 256) { for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } } value = context_w.charCodeAt(0); for (i = 0 ; i < 8 ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } else { value = 1; for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1) | value; if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = 0; } value = context_w.charCodeAt(0); for (i = 0 ; i < 16 ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } context_enlargeIn--; if (context_enlargeIn == 0) { context_enlargeIn = Math.pow(2, context_numBits); context_numBits++; } delete context_dictionaryToCreate[context_w]; } else { value = context_dictionary[context_w]; for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } } context_enlargeIn--; if (context_enlargeIn == 0) { context_enlargeIn = Math.pow(2, context_numBits); context_numBits++; } } // Mark the end of the stream value = 2; for (i = 0 ; i < context_numBits ; i++) { context_data_val = (context_data_val << 1) | (value & 1); if (context_data_position == bitsPerChar - 1) { context_data_position = 0; context_data.push(getCharFromInt(context_data_val)); context_data_val = 0; } else { context_data_position++; } value = value >> 1; } // Flush the last char while (true) { context_data_val = (context_data_val << 1); if (context_data_position == bitsPerChar - 1) { context_data.push(getCharFromInt(context_data_val)); break; } else context_data_position++; } return context_data.join(''); }, decompress: function (compressed) { if (compressed == null) return ""; if (compressed == "") return null; return LZString._decompress(compressed.length, 32768, function (index) { return compressed.charCodeAt(index); }); }, _decompress: function (length, resetValue, getNextValue) { var dictionary = [], next, enlargeIn = 4, dictSize = 4, numBits = 3, entry = "", result = [], i, w, bits, resb, maxpower, power, c, f = LZString._f, data = { val: getNextValue(0), position: resetValue, index: 1 }; for (i = 0; i < 3; i += 1) { dictionary[i] = i; } bits = 0; maxpower = Math.pow(2, 2); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } switch (next = bits) { case 0: bits = 0; maxpower = Math.pow(2, 8); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } c = f(bits); break; case 1: bits = 0; maxpower = Math.pow(2, 16); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } c = f(bits); break; case 2: return ""; } dictionary[3] = c; w = c; result.push(c); while (true) { if (data.index > length) { return ""; } bits = 0; maxpower = Math.pow(2, numBits); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } switch (c = bits) { case 0: bits = 0; maxpower = Math.pow(2, 8); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } dictionary[dictSize++] = f(bits); c = dictSize - 1; enlargeIn--; break; case 1: bits = 0; maxpower = Math.pow(2, 16); power = 1; while (power != maxpower) { resb = data.val & data.position; data.position >>= 1; if (data.position == 0) { data.position = resetValue; data.val = getNextValue(data.index++); } bits |= (resb > 0 ? 1 : 0) * power; power <<= 1; } dictionary[dictSize++] = f(bits); c = dictSize - 1; enlargeIn--; break; case 2: return result.join(''); } if (enlargeIn == 0) { enlargeIn = Math.pow(2, numBits); numBits++; } if (dictionary[c]) { entry = dictionary[c]; } else { if (c === dictSize) { entry = w + w[0]; } else { return null; } } result.push(entry); // Add w+entry[0] to the dictionary. dictionary[dictSize++] = w + entry[0]; enlargeIn--; w = entry; if (enlargeIn == 0) { enlargeIn = Math.pow(2, numBits); numBits++; } } } }; if (typeof module !== 'undefined' && module != null) { module.exports = LZString; }